Well drilling cable control



May 9, 1939.

H. w. BUSCHMAN WELL DRILLING CABLE CONTROL 3 Sheets-Sheet 1 Filed Sept. 24, 1938 May 9, 1939. H. w. BUSCHMAN WELL DRILLiNG CABLE CONTROL Filed Sept. 24, 1958 3 Sheets-Sheet 2 y 1939- H. w. BUSCHMAN 7 2,157,951

WELL DRILLING CABLE CONTROL 3,67 f 2 .W BZ5o man Patented May 9, 1939 UNETED STATES PATENT OFFME WELL DRILLING CABLE CONTROL Henry W. Buschman, Spearman, Tex.

Application September 24, 1938, Serial No. 281,598

11 Claims. (Cl. 25515) The present invention relates to the class of features of the invention as expressed in the well drilling and pertains particularly-to an imappended claims. proved apparatus for controlling the slack and In the drawings: take up of drilling cable. Figure l is a view in side elevation of a well The primary object of the present invention is drilling mechanism showing the device embody- 5 to provide a novel yieldable pulley mounting for a ing the present invention in connection therepulley over which a drilling cable passes, which with.

is so constructed and arranged that slack in the Figure 2 is a view in plan of the frame portion cable will be automatically taken up as the cable of the mechanism shown in Figure 1, a portion of is pulled and released by the controlling walking the walking beam having been removed. 10 or spudding beam so that the tension of the cable Figure 3 is a sectional view on the line 33 will always be kept the same and lost motion will of Figure 1. be eliminated thereby resulting in a speeding up Figure 4 is a view in side elevation of a well of the operation of the drill to make it possible to drilling mechanism showing a modified form of sink a well of a given depth in less time than can the invention in association therewith. 15 be done with ordinary methods and machinery. Figure 5 is a sectional view on the line 5-5 Another object of the invention is to provide in of Figure 4. well drilling machinery of the character referred Figure 6 is a sectional View on the line 6-45 to, an improved brake controlling means which is of Figure 5.

2O operated and controlled in accordance with the Figure 7 is a view in side elevation of a well amount of strain or pull applied to the drill cable, drilling mechanism showing another modificathe said brake being operated intermittently as tion of the invention in associated therewith. the cable controlling mechanism pulls and re- Figure 8 is a section taken on the line 88 of leases the cable for the raising and lowering or Figure 7.

dropping of the drill. Figure 9 is a view upon an enlarged scale of 25 Still another object of the invention is to prothe brake shoe actuating pump shown in Figure vide in well drilling machinery of the above 7. a p rti n of th pu p being in section described character, a brake controlling mecha- Figure 1 is & Sec a V ew Of the pp d nism including a supporting pulley over which of the drill cable supporting derrick showing the the well drill cable passes, which is operated by method of u g t u pressure Operated 30 and in accordance with the weight of cable susmeans for the brake thereon. pended from the pulley, means being provided Referring now more particularly to the drawwhereby a compensatory adjustment may be ings, there is illustrated in Figure 1, a well made in the mechanism as the length of the paid drilling mechanism which comprises a base frame out cable increases and consequently with an inl at the rear of which is a vertical frame 2 car; 35 crease of weight on the pulley, so that the operrying a transverse shaft 3. At the forwardend ation of the brake will be always the same. of this frame is the upright derrick structure 4 Still another object of the invention is to proof a suitable form for supporting at its top a. vide in a well drilling machine employing a rockcable crown pulley 5a ing walking beam or spudding beam, carrying a On the base frame is the usual mechanism for 40 drill cable pulley, a fluid operated brake mechaoperating the drill, which mechanism comprises nism which is controlled by a limited relative bearings B supporting a horizontal shaft l on movement between the pulley and the walking which is carried the Walking beam driving wheel beam as the walking beam swings for effecting which is conventionally illustrated and indicated the raising and dropping of the drill cable and by the um Behind a j c t e 45 the drill carried thereby. wheel 8 is. a brake pulley 9 which is supported The invention will be best understood from a upon a transverse shaft lil, one end of the shaft consideration of the following detailed descripcarrying the gear pinion ifla. While the other end tion taken in connection with the accompanying is supported upon the oscillatable bearing [0 drawings forming part of this specification, with which may be moved back and forth to shift the b the understanding, however, that the invention is brake pulley 9 relative to the periphery of the not to be confined to any strict conformity with wheel 8, by the control mechanism C which is the showing of the drawings but may be changed pivotally mounted upon a suitable part of the or modified so long as such changes or modificastructure as shown. The numeral I I generally tions mark no material departure from the salient designates the drill cable drum on which the 55 drill carrying an operating cable 82 is wound, the cable passing around the idler pulley 53, supported on the shaft 3, and passing forwardly over and longitudinally of the walking beam i to pass around and under the automatic feeler or take-up pulley unit embodying a portion of the present invention and indicated generally by the numeral l5. From this unit the cable passes upwardly over the crown pulley 5 and down into the drill hole into the ground. The drum ii is connected with the gear lid and the wheel 8 is driven by the belt B connected with a driving pulley P which receives power from a suitable source and to those familiar with the art, it will be recognized that the drill cable 52 iswound up so as to remove the drill from the ground by actuating the mechanism C to shift brake pulley 9 into contact with the constantly rotating wheel 8, thus transmitting rotary motion to the drum i I to turn the latter in the direction necessary to wind up the cable.

Supported in a suitable bearing adjacent the periphery of the brake pulley 2 is a stub shaft 56 which carries a brake shoe i'i disposed for contact with the periphery of the wheel 9 when oscillated in one direction so as to maintain the brake pulley against rotation. It will be recognized that when the brake shoe is in contact with the pulley, the mechanism will be adjusted so as to swing the brake pulley out of contact with the wheel 8 and toward the brake shoe with which it has engagement. The brake shoe may be released from engagement with the rake pulley 9 by effecting the oscillation of the shoe through the medium of the rod l3. Under normal operation of the mechanism, the wheel 8 runs constantly so as to effect the desired vertical reciprocation of the walking beam i i through the medium of the usual crank and pitman 39 and the brake i? may be maintained by the operation of the control rod l8 in constant engagement with the brake pulley Q so as to prevent any rotary movement of the drum ii, thus making it possible for the walking beam to pull and release the cable l2 so as to raise and lower the drill to which it is attached. When necessary to pay out cable, the brake can be released so that the pulling action of the walking beam will withdraw some of the cable from the drum whereupon the brake shoe will be again engaged and, as previously stated, when it is necessary to draw up the cable and the drill, then the mechanism C is operated to shift the brake pulley into contact with the wheel 8 so as to transmit the desired rotary motion to the drum The automatic feeder or cable take up unit, indicated generally by the numeral l5, comprises a casting I9 which, when the walking beam is made up of the two parallel members i i, as shown, is positioned between the free ends of these members in the manner illustrated. This casting l9 has a vertically disposed and transversely extending passage 28 therethrough in which is located a block 25 which is of a length to engage at its ends against the opposing faces of the members id but is of a width materially less than the height of the passage 28 in which it is positioned so that, being secured to the walking beam members [4 by bolts 22 it may move up and down in the passage, as hereinafter described.

The lower portion of the casting is is reduced and made circular, as indicated at 23, and integral with this reduced portion is a threaded downwardly extending stem 24 which passes through a plate 25 which is retained thereon by the nut .26 which is threadably connected with the stem as shown. Interposed between the plate 25 and the casting i9 is a heavyexpansion spring 27, the upper end of which encircles the reduced portion 23 of the casting, while the lower end rests upon the plate 25. Thus, it will be seen that when the block 21 is shifted downwardly in the passage 26, it will come against the upper end of the spring 21 and the downward movement which the block will then transmit to the casting 69 will be through this spring, the spring operates as a shock absorber and slack take up for the cable, as hereinafter described.

The upper portion of the casting I9 is formed to provide a pulley yoke 23 in which is pivotally supported the sheave 29 around which the cable i2 passes.

From this form of the invention it will be seen that as the walking beam has its: free end swung up and down through the medium of the crank and pitman 36 which connects it with the wheel 8 the down pull of the walking beam will first effect the movement of the block 2! against the spring 21 and the motion will then be transmitted through this spring to the casting Hi to effect the desired pull upon the cable 12 for the raising of the drill. As the walking beam rises, it will be apparent that the reaction effect of the spring 2? will be to hold back on the cable l2 so that the sheave 29 will not be thrown upwardly so rapidly as to allow slack to develop in the cable.

Attached to the face of the yake 28 is a cable shield 3! which partially surrounds the sheave or pulley and operates to prevent the cable slipping off.

In Figure 4 there is illustrated a modifiedform of the automatic take up or feeler feed wherein the control of the brake pulley shoe is made automatic to be applied and released as is necessary, with the rise and fall of the walking beam. In this form of the invention the base frame is indicated by the numeral 32 and the operating wheel for the walking beam is designated by the numere point adjacent the longitudinal center of the frame 32 and which is connected at its inner end with the pedal All) which extends forwardly from the frame for the purpose hereinafter set forth.

This rod 37 passes through a fixed guide ll and forwardly of this guide there are threaded upon the rod a spring tension controlling nut 52 and a lock nut Q3 and between the nut 32 and the fixed rod guide is a coil spring 44 which surrounds the guide and normally operates to shift the rod El in a direction to maintain the brake 36 applied against the pulley 35.

The derrick structure comprises the two vertical beams 45 which are disposed upon the longitudinal center of, the frame 32 and which have fixed to their upper ends, the vertical channel upper ends by straps 41. Secured between the vertical channel beams 46 at a substantial distance below the straps 41 is a fixed saddle 48 having a central opening through which the upper end of a rod, indicated generally by the numeral 4-9, passes, this rod from its upper end down through approximately half its length being of greater diameter than the lower portion and the upper portion is indicated by the numeral 50,

while the lower portion which is of smaller diameter is indicated by the numeral 5!. The saddle 49 operates as a guide for the upper end of the rod 50 and also as a support for a spring 52, the upper end of which abuts a sliding saddle 53 in which the upper end of the rod 49 is fixed. The sliding saddle carries the two Vertical members 54 which together form a yoke for a pulley 55, the upper ends of the members 54 being formed to provide suitable bearings for the shaft '55 to which the pulley is secured.

The upper portion 59 of the rod 49 is screw threaded adjacent its lower end, as indicated at 51, to receive the nuts 59 and 59, the lower one of which has the upper end of a coil spring 69 engaged thereagainst, the spring resting upon a fixed support 6| which is secured across the lower portion of the derrick between the members 45 and which has an aperture through which the lower part 5| of the rod 49 passes.

The rod 49 is disposed vertically between the upright parts 45 and 45 which make up the derrick structure, above the pedal 40, and the lower end of the lower portion 5| of the rod has threaded thereon the elongated nut 62 at the upper end of which is a locking nut 53. By suitably adjusting the nut 52 upon the rod, the effective length of the latter may be changed so that the oscillation of the pedal by the rod in the manner hereinafter described maybe made to take place after a relatively short movement of the rod or after a long movement thereof as may be desired.

With this second form of the invention, it will be apparent that the springs 52 and 59 must sustain the weight of that portion of the drill cable extending from the pulley 55 downwardly to the drilling tool and must also sustain the weight of the tool which the cable carries. As the drilling operation proceeds and the bit goes down into the earth, the bit will be raised and lowered by the walking-beams and the springs 52 and 59 operate as cushions to take up the slack in the cable thus keeping the cable always at an even tension as the walking beam operates to pull the cable and release it as the hole goes deeper. As the hole deepens, the weight on the springs increases until the pressure or weight is sufficient to force the rod 49 downwardly and into engagement with the trigger 49, as shown in Figs. l and 5. When the rod presses against the trigger 49, this effects an oscillation of the lever 98 and rearward movement of the rod 37 to swing the brake shoe 35 away from the brake pulley 35. This movement of the push rod immediately precedes the last stroke of the bit and when the brake is released as soon as the rebound of the bit takes place, the drum will be freed and allowed to rotate so that some of the cable can be drawn off. As soon as some of the cable is drawn from the drum, the springs 52 and 69 react to lift the pulley sheave and take up the slack, thus releasing the pedal 49 andallowing the shoe 36 to re-engage the brake pulley preventing further rotation of the drum and removal of cable therefrom. The drilling operation then goes forward as before, until the previously described condition is re-established requiring the withdrawal of more cable.

In the modified form of the invention just described, the walking beam indicated by the nu.- meral 34, carries upon its forward or free end a pulley 65 of ordinary form across the underside of which the cable 66 passes before it extends up and over the crown pulley 55 which is supported upon the upper end of the vertically movable rod 49.

In Figure '7 there is illustrated a still further modification of the invention wherein the brake shoe operating means is controlled by fluid pressure which is built up and released by mechanism carried by the pulley unit supported upon the free end of the machine walking beam, the pulley unit being of substantially the same form as that indicated by the numeral I5 but having certain additional features incorporated therein. In this fluid pressure operate-d brake control means, the frame is generally designated by the numeral 61, the rear portion 68 carrying a shaft 69 on which is mounted an idler pulley 10 across which the drill tool operating cable H passes. The walking beam 12 is supported at one end upon the shaft 69 and consists of the two channel iron members 12' disposed in spaced parallel relation as in the other forms. The driving pulley for the walking beam is indicated by the numeral 13 and is connected by the crank and pitman 14 with the walking beam, the brake pulley which is connected with the driving pulley or wheel being indicated by the numeral 15.

The numeral 16 designates the brake shoe which is oscillatably supported upon the shaft 77 adjacent the pulley l5 and upon opposite sides of the shoe there are attached to the frame 61, the fixed brackets 18 and 19. To one of these brackets, here shown as the bracket 18, there is secured a cylinder 80 from which projects ,through the end nearest the brake shoe 16, a

piston 8| which abuts the shoe. The brake shoe is constantly maintained against the outer end of the piston Bl by the expansion spring 82 which is interposed between the other side of the brake shoe from the piston and the fixed bracket 19.

A pipe coupling 83 is connected with the cylinder 80 and from this coupling there extends the pipe 84 which leads to the flexible hose 85 which is supported adjacent the shaft 59 and from this flexible hose which is in the form of an elbow, there extends the pipe 86 which leads forwardly along one side of one of the members 72 of the walking beam 12, to the forward or free end of this beam where it connects with the fixed elbow coupling 81.

The pulley unit supported at the free end of the walking beam 12 is indicated as a whole by the numeral 98 and comprises a casting 89 having a transverse passage or recess 99 therein and formed integral at its top with the pulley yoke 91 in which is pivotally suported the pulley wheel 92. Extending downwardly from the underside of this casting is a reduced threaded extension 93 which carries a supporting plate 94 for the coil spring 95, the plate being secured in position by the nut 95 and the upper end of the coil spring bearing against the body of the casting and extending partly over the ends of the passage 99 so as to be engaged by the sliding block 91 which extends transversely through the passage 99 and which is secured at its ends to and between the members E2 of the walking beam 72, by the bolts 98. The block 9'! has secured\ therein the vertical piston cylinder 99 in which is a piston I00, the lower end of which extends below the lower edge of the block 01 to be engaged by the bottom wall of the recess when the block 91 moves down relative to the casting in which it is carried. Within the cylinder 09 is a spring IOI which normally forces the piston I outwardly and the upper end of the cylinder is connected with the coupling 31 by the oil tube I02. With this construction it will be readily apparent that the operation of the mechanism is substantially the same as that described in connection with the mechanism illustrated in Figs. 4 and 5, in that the strength and tension of the spring 95 will be sufficient to eifect the lifting of the cable and drill during the ordinary operation of the mechanism but that as the depth of the drill hole increases, the point will be finally reached where the drill will not be able to dig deeper in the ground whereupon a sufficiently violent jerk or rebound will be made to occur which will effect the compression of the spring 95 sufiiciently to drive the stem of the piston I00 against the lower part or wall of the recess 90 and thus eifect the compression of fluid in the cylinder 09 and the transmission of such pressure to the cylinder 80 and the piston 8|. This will result in the projection of the piston BI and the oscillation of the brake shoe I6 away from the brake pulley I5, thus releasing the cable drum and permitting a certain amount of cable to be wound off. As soon as the required amount of cable has been wound off, then the spring 82 will re-set the brake shoe against the brake pulley l forcing the piston BI back to its former position and re-setting piston I00 for the next stroke when required.

In Figure there is shown a means for operating or controlling the brake pulley shoe by hydraulic pressure from the crown pulley of the "derrick. In this view theupper members or upper portions of the derrick members are shown and indicated by the numeral I03 and between these members the crown pulley I04 is supported in the yoke I05 for limited sliding movement, carrying with it the pin I06. The lower part of this yoke includes a cross bar I01 between which and a fixed cross member or spring rest I08, the spring I06 is held. Beneath the fixed spring rest I08 is a pump support I00 carrying the pump cylinder H0 from which extends upwardly the piston III. This pump cylinder is connected by the fluid pipe line II2 with the piston and cylinder unit associated with the brake pulley brake shoe in the same manner as described in connection with the structure shown in Figure '7, and it will be readily apparent that as the crown pulley I04 is forced down by reason of pressure applied thereto through the medium of the drill cable when the walking beam of the mechanism is pulled down for the raising of the drill, the pin I06 will strike the piston III and force fluid through the line II2 to release the brake shoe.

From the foregoing it will be readily apparent that with the device embodying the present invention installed in a Well drilling mechanism of the character described and in the manner described, the slack occurring at intervals in. the drill cable will be automatically taken up and the tension of the cable therefore maintained constant or even at all times. In addition, this slack take up means has been employed for automatically releasing the brake pulley of the mechanism at the moment in the operation of the same when such release is desired.

. I claim:-.

1. In well drilling mechanism of the character described, including a derrick and a vertically oscillatable walking beam, a pulley unit mounted upon said derrick above the walking beam, a pulley unit carried by said Walking beam, said pulley units being designed to have a drill tool carrying cable passed thereacross, means associated with and supporting one of said pulley units whereby the unit may have limited vertical movement and is constantly urged to move in a direction to maintain a taut condition in said cable, pay out means for the cable, means normally preventing the paying out of cable, and mechanism connected between the said one pulley unit and the pay out means operating to release said means upon movement of the said one pulley oppositely to the direction in which it is urged.

2. In a well drilling mechanism of the character described including a derrick, a crown pulley carried by the derrick, a pivotally mounted vertically oscillatable walking beam, a pulley carried by said beam, drive means connected with said beam for effecting the oscillation thereof and a cable passing across said pulleys from a rotatable supporting drum to a drill tool, means forv taking up slack in the cable consisting of a vertically movable support for one of said pulleys, resilient means normally urging the movement of said support in a direction to maintain the cable in taut condition, brake means normally holding said drum from rotation, and mechanism connected with said brake means andactuated to release the latter upon the movement of the said one of the pulleys a predetermined distance in opposition to the resilient means associated therewith.

3. In a well drilling mechanism of the'character described, including a vertically oscillatable Walking beam, a drill tool cable pulley unit carried by said walking beam comprising a casting, a pulley sheave rotatably carried by said casting, said casting having an opening therein, a block disposed in said opening, connecting means between the block and the walking beam, and spring means carried by the casting and arranged to be engaged and compressed by said block upon downward movement thereof with the walking beam relative to the casting.

4. In a well drilling mechanism including a derrick, a rotatable cabledrum, a walking beam pivotally mounted at one end and having its other end disposed adjacent to the derrick, drive means connected with said walking beam for effecting the vertical oscillation of the same, brake means normally holding said drum from rotation, drill cable guide pulleys carried by the said free end of the Walking beam and by said derrick, one of said pulleys being resiliently supported and adapted to be shifted against the ten sion of the resilient support when strain is applied to the drill cable passing thereover, and means made operative upon the shifting of the said one of the pulleys against the resilient means to effect the release of said brake.

5. A well drilling mechanism comprising a frame, a derrick adjacent the frame, a rotatable cable drum, a walking beam having one end piV- otally mounted upon the frame and the other end disposed adjacent the derrick for vertical oscil-' lation,'means for effecting oscillation of the beam, a brake pulley geared to said drum, a brake shoenormally engaging said pulley, a cable pulley carried upon the free end of the walking beam, a crown pulley for the cable supported upon said derrick, means connecting the crown pulley with the derrick facilitating limited vertical movement of the crown pulley, resilient means normally urging the crown pulley upwardly, and means for effecting the release of said brake upon movement of said crown pulley a'predetermined distance downwardly against the tension of the said resilient supporting means.

6. A well drilling mechanism comprising a derrick structure, a frame adjacent said derrick structure, a rotatable cable drum, a walking beam pivotally connected at one end with the frame and having its other end adjacent the derrick and adapted to be oscillated vertically, means for oscillating said walking beam, a brake pulley geared to said drum, a brake shoe normally engaging the pulley, a pulley unit supported upon the free end of the walking beam, a crown pulley supported upon said derrick, said pulley unit and crown pulley having a drill tool cable passed thereabout, means forming a resilient movable connection between said pulley unit and the walking beam whereby said pulley unit and walking beam may move relatively, and fluid pressure operated means made operative upon the movement of said walking beam and pulley unit a predetermined relative distance for releasing said brake shoe from contact with the brake pulley.

7. In a well drilling mechanism of the character described, a pivotally mounted walking beam having an end movable vertically, a derrick structure adjacent said end of the walking beam, means for actuating said walking beam, a brake pulley, a cable drum having driven connection with the pulley, a drill tool cable guiding pulley supported upon the said end' of the walking beam, a pulley yoke supported by said derrick for vertical movement, a cable guide pulley carried by said yoke, resilient means normally urging said pulley yoke upwardly against the weight of a cable passing thereover, a rod member extending downwardly from said yoke, a brake shoe normally engaging said brake pulley, and means connected with said brake shoe whereby a downward movement of said derrick carried pulley a predetermined distance will eifect the release of said brake shoe through the longitudinal movement of said rod.

8. A well drilling mechanism of the character described comprising a walking beam pivotally mounted for vertical oscillation, a derrick disposed adjacent the walking beam, means for effecting the oscillation of the walking beam, a brake pulley, a rotary cable drum having driving connection with said pulley, a brake shoe normally engaging said pulley, a drill tool actuating cable wound at one end on the drum, a pulley unit for said cable supported upon said walking beam, a pulley unit for said cable supported upon the derrick, fluid pressure operated actuating means for and connected with said brake, supporting means for one of said pulley units whereby limited vertical movement of the unit is permitted, resilient means normally urging the movement of the said one of the pulley units upwardly against weight imposed thereon by the drill tool and cable, a fluid pump associated with the said one of the pulley units and arranged to be made operative for the ejection of fluid therefrom upon downward movement of the said one of the pulley units a predetermined distance, and a fluid line connecting said pump with said fluid pressure operated brake actuating means whereby fluid ejected from said pump will actuate said brake actuating means to release the brake.

9. A well drilling mechanismof the character described, comprising a walking beam pivotally mounted at one end for vertical oscillation, a derrick structure adjacent the other end of the walking beam, means for efiecting the oscillation of the walking beam, a brake pulley, a cable drum geared to the pulley, a brake normally applied to said pulley, an actuating rod for the brake extending therefrom to a point adjacent the lower part of said derrick and having an operating pedal connected therewith, means in the upper part of said derrick forming a pulley guide, a pulley mounted for vertical movement in said guide, a rod connected with said pulley and extending downwardly to a point adjacent said pedal, resilient means normally urging the upward movement of said pulley, a pulley mounted upon said walking beam adjacent the free end thereof, said pulleys operating as guides for a drill tool cable, and said derrick carried pulley being shiftable downwardly upon the application of a predetermined Weight of cable and drill and shifting said rod into contact with said pedal to effect the release of said brake.

10. In a well drilling mechanism including a derrick and a vertically oscillatable walking beam, a pulley unit mounted on the derrick above the walking beam, a body carried by and fixed to the walking beam to be moved vertically therewith,

a pulley unit supported by said body, resilientmeans interposed between the pulley unit and the adjacent body and normally urging the unit downwardly with respect to the body, the units being designed to have a drill tool carrying cable passed thereacross from a pay out source, said beam carried unit being moved up against the resilient means by the resistance of the cable at periods in the operation of the mechanism when the beam moves down, a normally applied brake holding said pay out means, a fluid actuated piston operatively connected with the brake, a fluid impeller carried by the beam carried body and engaged by the adjacent unit to eject fluid when the unit is moved down, and a fluid line'connected between the impeller and piston whereby the piston is moved to release said brake upon downward movement of the beam carried unit.

11. In a well drilling mechanism including a derrick and a vertically movable walking beam, a pulley unit mounted upon the walking beam to be moved vertically thereby, a pair of spaced guides supported vertically upon the upper end of the derrick, a pulley unit mounted between said guides for vertical movement, the said pulley units being designed to have a drill tool carrying cable passed thereacross from a pay out source, a normally applied brake means holding said pay out source against the release of cable therefrom, a fluid operated piston connected with said brake and acting when operated to release the brake, a fluid impeller supported upon the derrick beneath the vertically movable pulley unit, said impeller including a vertically disposed reciprocable stem, resilient means normally urging said vertically movable unit upwardly from said impeller, a plunger carried by the vertically movable unit in line with said stem and operating to engage the stem when the adjacent unit is moved down for the ejection of fluid from the impeller, and a fluid line coupling said impeller with said fluid operated piston.

HENRY W. BUSCHMAN. 

